In some cases, patients with heart failure are treated with cardiac resynchronization therapy (CRT), which is a form of cardiac pacing. In some examples, CRT involves delivery of pacing pulses to both ventricles (“biventricular pacing”) to synchronize their contraction. In other examples, CRT involves delivery of pacing pulses to one ventricle to synchronize its contraction with that of the other ventricular, such as pacing the left ventricle to synchronize its contraction with that of the right ventricle.